Collapse internal revalidation requests (SMP-unaware caches), again.

[thirdparty/squid.git] / src / http.h

diff --git a/src/http.h b/src/http.h
index 44bee1844528902df12457dc57e3d579b6767002..42e5d443cbe61bfc1e484f4083b43708b3c3048b 100644 (file)
--- a/src/http.h
+++ b/src/http.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1996-2014 The Squid Software Foundation and contributors
+ * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
  *
  * Squid software is distributed under GPLv2+ license and includes
  * contributions from numerous individuals and organizations.
@@ -11,9 +11,10 @@
 
 #include "clients/Client.h"
 #include "comm.h"
-#include "HttpStateFlags.h"
+#include "http/forward.h"
+#include "http/StateFlags.h"
+#include "sbuf/SBuf.h"
 
-class ChunkedCodingParser;
 class FwdState;
 class HttpHeader;
 
@@ -22,6 +23,23 @@ class HttpStateData : public Client
     CBDATA_CLASS(HttpStateData);
 
 public:
+
+    /// assists in making and relaying entry caching/sharing decision
+    class ReuseDecision
+    {
+    public:
+        enum Answers { reuseNot = 0, cachePositively, cacheNegatively, doNotCacheButShare };
+
+        ReuseDecision(const StoreEntry *e, const Http::StatusCode code);
+        /// stores the corresponding decision
+        Answers make(const Answers ans, const char *why);
+
+        Answers answer; ///< the decision id
+        const char *reason; ///< the decision reason
+        const StoreEntry *entry; ///< entry for debugging
+        const Http::StatusCode statusCode; ///< HTTP status for debugging
+    };
+
     HttpStateData(FwdState *);
     ~HttpStateData();
 
@@ -29,7 +47,7 @@ public:
                                        StoreEntry * entry,
                                        const AccessLogEntryPointer &al,
                                        HttpHeader * hdr_out,
-                                       const HttpStateFlags &flags);
+                                       const Http::StateFlags &flags);
 
     virtual const Comm::ConnectionPointer & dataConnection() const;
     /* should be private */
@@ -39,13 +57,13 @@ public:
     void readReply(const CommIoCbParams &io);
     virtual void maybeReadVirginBody(); // read response data from the network
 
-    // Determine whether the response is a cacheable representation
-    int cacheableReply();
+    // Checks whether the response is cacheable/shareable.
+    ReuseDecision::Answers reusableReply(ReuseDecision &decision);
 
-    CachePeer *_peer;          /* CachePeer request made to */
-    int eof;                   /* reached end-of-object? */
-    int lastChunk;             /* reached last chunk of a chunk-encoded reply */
-    HttpStateFlags flags;
+    CachePeer *_peer;       /* CachePeer request made to */
+    int eof;            /* reached end-of-object? */
+    int lastChunk;      /* reached last chunk of a chunk-encoded reply */
+    Http::StateFlags flags;
     size_t read_sz;
     SBuf inBuf;                ///< I/O buffer for receiving server responses
     bool ignoreCacheControl;
@@ -84,9 +102,22 @@ private:
     virtual bool getMoreRequestBody(MemBuf &buf);
     virtual void closeServer(); // end communication with the server
     virtual bool doneWithServer() const; // did we end communication?
-    virtual void abortTransaction(const char *reason); // abnormal termination
+    virtual void abortAll(const char *reason); // abnormal termination
     virtual bool mayReadVirginReplyBody() const;
 
+    void abortTransaction(const char *reason) { abortAll(reason); } // abnormal termination
+
+    /**
+     * determine if read buffer can have space made available
+     * for a read.
+     *
+     * \param grow  whether to actually expand the buffer
+     *
+     * \return whether the buffer can be grown to provide space
+     *         regardless of whether the grow actually happened.
+     */
+    bool maybeMakeSpaceAvailable(bool grow);
+
     // consuming request body
     virtual void handleMoreRequestBodyAvailable();
     virtual void handleRequestBodyProducerAborted();
@@ -109,16 +140,23 @@ private:
 
     /// Parser being used at present to parse the HTTP/ICY server response.
     Http1::ResponseParserPointer hp;
-    ChunkedCodingParser *httpChunkDecoder;
+    Http1::TeChunkedParser *httpChunkDecoder;
 
     /// amount of message payload/body received so far.
     int64_t payloadSeen;
     /// positive when we read more than we wanted
     int64_t payloadTruncated;
+
+    /// Whether we received a Date header older than that of a matching
+    /// cached response.
+    bool sawDateGoBack;
 };
 
+std::ostream &operator <<(std::ostream &os, const HttpStateData::ReuseDecision &d);
+
 int httpCachable(const HttpRequestMethod&);
 void httpStart(FwdState *);
-const char *httpMakeVaryMark(HttpRequest * request, HttpReply const * reply);
+SBuf httpMakeVaryMark(HttpRequest * request, HttpReply const * reply);
 
 #endif /* SQUID_HTTP_H */
+